A duplexer is a device that facilitates bi-directional communication (i.e., simultaneous reception and transmission) by a common antenna. In order to facilitate simultaneous reception and transmission of signals over the antenna, the duplexer needs to be designed for operation at both receive and transmission bands while providing adequate isolation between receive and transmission signals. To provide multi-mode and multi-band operation, radio frequency (RF) duplexers often use multiple parallel duplexer components selected using an ever-growing number of switches. As such, this type of RF duplexer solution presents ever-increasing demands with regard to cost and size.
Accordingly, more adaptable RF duplexers are needed to provide multi-band/multi-mode operations that do not require increases in cost and size.